Anion-exchange membrane water electrolysis is a promising technology for economical green hydrogen production; however, the corresponding industrial applications are limited by the lack of reliable polymer electrolytes. To address this problem, we developed chain-extender-derived high-molecular-weight hexyltrimethylammonium-tethered polycarbazoles (HQPC-TMA-x's) with compelling membrane characteristics, including high ionic conductivity, mechanical robustness, and high alkaline stability. Owing to its polycarbazole backbone, HQPC-TMA-x alleviated the problems due to ionomer adsorption on the electrode. In the single-cell configuration, the best-performing polymer (HQPC-TMA-2.4) achieved an unprecedented current density of 14.6 A cm⁻² at 2.0 V with a Ni–Fe alloy anode and low-cost cell hardware, additionally showing superior pure-water-electrolysis and direct-seawater-electrolysis performances. HQPC-TMA-2.4 exhibited in situ durability at a high current density of 1.0 A cm⁻² for 1000 h with low irreversible degradation rates of 52 and 6 μV h⁻¹ for platinum group metal (PGM) and PGM-free cells, respectively, demonstrating the reliability of this polymer in practical settings.

中文翻译：

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采用高分子量聚咔唑基阴离子导电聚合物的高性能、耐用的阴离子交换膜水电解槽

阴离子交换膜水电解是一种很有前景的经济绿色制氢技术；然而，由于缺乏可靠的聚合物电解质，相应的工业应用受到限制。为了解决这个问题，我们开发了扩链剂衍生的高分子量己基三甲基铵系聚咔唑 (HQPC-TMA- x 's)，其具有引人注目的膜特性，包括高离子电导率、机械鲁棒性和高碱性稳定性。由于其聚咔唑主链，HQPC-TMA -x缓解了电极上离聚物吸附造成的问题。在单电池配置中，性能最佳的聚合物 (HQPC-TMA-2.4)在 2.0 V 下使用 Ni-Fe 合金阳极和低成本电池硬件实现了前所未有的 14.6 A cm ^-2电流密度，此外还表现出优越的性能纯水电解和直接海水电解性能。 HQPC-TMA-2.4在1.0 A cm ^-2高电流密度下表现出原位耐久性1000小时，铂族金属（PGM）和无PGM电池的不可逆降解率分别为52和6 μV h ^-1，证明了这种聚合物在实际环境中的可靠性。